When using an Amazon Web Services RDS instance from a Java application, what is the best JDBC connection string?
It should tolerate the instance falling over to the standby. AWS handles flipping the CNAME to point from the primary to standby under the hood.

1 Answer
1

During certain types of planned maintenance, or in the unlikely event
of DB Instance failure or Availability Zone failure, Amazon RDS will
automatically failover to the standby so that you can resume database
writes and reads as soon as the standby is promoted. Since the name
record for your DB Instance remains the same, you application can
resume database operation without the need for manual administrative
intervention. With Multi-AZ deployments, replication is transparent:
you do not interact directly with the standby

As long as you have your RDS instance in multi-AZ, you are good with the jdbc url of the RDS instance FQDN.